Large-scale antennas are used to enhance coverage of a system, eliminate inter-user interference, reduce number of websites and lower cost of operation and maintenance, which is one of hot candidate technologies in an LTE-A system. Vertical sectorization technology and user 3-dimensional beamforming technology are technologies which are relatively easily industrialized in a large-scale antenna system. FIG. 1 shows a schematic diagram of the vertical sectorization technology; wherein user equipment 104 is spatially multiplexed and a capacity of the system is improved by beamforming by a base station end 102. FIG. 2 shows a schematic diagram of the user 3-dimensional beamforming technology; wherein by beam alignment by the base station end 102, the user equipment 104 is enabled to acquire a higher beamforming gain, and interference between the user equipment 104 is reduced; furthermore, the system is able to support a multi-user multi-antenna technology with more data streams, and the user equipment 104 is spatially multiplexed, further improving the capacity of the system. However, all these technologies need that spatial resolution of the system is increased, that is, the system needs to use more antenna ports.
However, as an LTE-A R10/11 system supports only at most 8 antenna ports, support of more antenna ports by channel state information reference signals (CSI-RSs) cannot be realized, hence, as the increase of the number of antennas, a limited number of antenna ports restricts the performance of the large-scale antenna system.